The invention relates to a method for producing a component and a component produced in such a way.
In the case of heavily stressed components such as, for example, blades of compressors or turbines, rotating components such as crankshafts, components with cyclical loads such as connecting rods, components of a static type with high thermal stress such as, for example, cooling structures as well as in the case of tools, it is frequently necessary to make a compromise between different and opposing requirements. Examples of this are high fatigue strength with a low weight or low brittleness with great hardness.
In order to meet these opposing requirements, the components are increasing being produced from metal alloys, which are only able to be processed to a limited extent using conventional production methods. In addition, it is disadvantageous that, for the most part, the entire base body of the component is made of this metal alloy so that individual component regions are not able to be optimized individually depending upon the load that occurs. Moreover, most of the time the metal alloy is restricted to a consideration of structural properties such as fatigue strength and weight. To achieve, for example, a high level of abrasion resistance or temperature resistance, the component is usually coated with a corresponding protective layer, which is applied during a subsequent and therefore additional production method. Thus, for example U.S. Pat. No. 6,365,222 B1 proposes coating a blade ring of a compressor with an abradable protective layer using gas dynamic cold spray. In doing so, a bonding layer is first applied to the base body and then the protective layer. In addition, gas dynamic cold spray for repairing turbine blades is also known from U.S. Pat. No. 6,905,728 B1. In this case, chips are filled with a corresponding material using gas dynamic cold spray and then the blade regions repaired in this manner are strengthened.
However, the disadvantage of the aforementioned gas dynamic cold spray method is that the applied layers are able to positively influence only external properties such as temperature resistance and abrasion resistance of the component. Structural properties such as an increase in the fatigue strength cannot be achieved with known gas dynamic cold spray methods. An additional disadvantage is that the conventional production methods greatly limit the shape or geometry of the components, which in turn may have a disadvantageous impact on component properties.
The object of the present invention is creating a method for producing a component, which eliminates the aforementioned disadvantages and which has individualized component regions adapted to a respective load, and a component produced in this manner having optimized component regions.
In the case of a method according to the invention for producing a component, at least one load line of the component is calculated. Then a core for the component is made available. Finally, a layer is applied on the core at least in sections by gas dynamic cold spray, wherein at least one layer section is produced in the layer, the material and orientation of the layer section being selected according to the load line.
The advantage of the method according to the invention is that it is possible to optimally dimension the component in accordance with its required properties. The core is virtually used merely as the substrate or carrier for the layer, in which the required properties are integrated based on the different materials and taking the respective load lines into consideration. Thus, for example component regions having a high fatigue strength may be made of a different material and have a different geometry than component regions having a high temperature resistance. According to the invention, a hybrid-like layer is created, which is optimally adapted to the mechanical loads so that it is also possible to combine actually opposing requirements in an optimal manner. It is no longer necessary to provide and fasten separate structural reinforcing structures. Due to the type of gas dynamic cold spray technique according to the invention, relatively soft and virtually organic transitions spilling over into each other are created between the different materials. Transitions of this type prevent a formation of steps and therefore make a harmonic load initiation and load distribution in or over the component possible. Another advantage is that only one production method is used to form the component and namely gas dynamic cold spray. Therefore, the use of several different methods is not required.
In the case of one exemplary embodiment, the layer is applied in different layer thicknesses. This allows a flexible design of the component shape or of component areas independent of the shape and size of the core. In doing so, the layer thickness may definitely range in the centimeter range so that for example rib-like reinforcing elements are produced.
Producing the layer section may be carried out strip-like in a width corresponding to a coverage distribution of a sprayed stream or by means of a mask covering the areas during spraying on which no material is supposed to be applied.
In the case of one exemplary embodiment, several layer sections are applied, the interstices of which are filled at least sporadically with a different material. An optimal load structure is hereby produced, the progression of which corresponds to the load lines, wherein the material in the interstices serves to stabilize the layer sections along with purely leveling them out.
In the case of one exemplary embodiment, a plurality of layers is applied. Thus it is conceivable for example to apply a top layer that defines a closed surface or outer surface of the component.
To achieve a final contour, the component may undergo an abrasive and/or strengthening post-processing.
A component according to the invention has a core, which has, at least in sections, a layer applied by gas dynamic cold spray. According to the invention, the layer has at least one layer section, the material and orientation of which are selected according to at least one calculated load line.
Such a component has optimum component properties and can be produced in almost in every shape or having every geometry.
The layer preferably surrounds the core completely so that the material and the shape of the core are almost freely selectable and the core may be designed for example to be optimized in terms of weight and/or have optimal adhesion conditions for the layer to be applied.
A plurality of layer sections is preferably provided for forming a load structure, which are able to form dendritic and/or organic structural sections for harmonic load initiation and load distribution.
In the case of one exemplary embodiment, the materials of at least some structural sections differ. The materials may hereby be adjusted individually to the loads.
The core, which may be both surface-like as well as skeletal or scaffold-like, may be made of almost any material. In the case of one exemplary embodiment, it is made of a different material or different materials than the layer.
Other advantageous exemplary embodiments are the subject matter of further dependent claims.
In addition, the method according to the invention may also be used, if, for example, components need to be labeled without negatively affecting the strength properties thereof. Examples of this are the tamper-proof labeling of metallic or hybrid components with a manufacturer's logo or serial numbers. The method according to the invention may likewise be used in the aesthetic or practical design of everyday articles such as knife blades and jewelry.
Preferred exemplary embodiments of the invention are explained in greater detail in the following on the basis of schematic representations.